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II. Development of Global Activities

II. Development of Global Activities

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NEW DIRECTIONS IN PLANT GENETIC RESOURCES



63



agricultural development. This loss of diversity, or genetic erosion of the

crop gene pools, was largely the loss of primitive populations, or land

races, which had evolved over long periods of time under conditions of

peasant agriculture. Certain regions of the world showed rich diversity for

particular crops and traditionally plant breeders had been able to obtain

materials from these regions for testing and use in crossing. The knowledge that this would become increasingly difficult led to proposals to

collect and conserve samples of important staple crops, especially since

the revolution stemming from the ever wider adoption of new high-yielding

varieties of wheat and rice. At that time we saw the foundations laid for the

establishment of international agricultural research centers (IARCs)

which, in 1971, were to be associated into the Consultative Group on

International Agriculture Research (CGIAR).

In relation to crop genetic resources, the Food and Agriculture Organization (FAO) took a lead role in pointing to the needs and identifying

priorities for collection and conservation; collaboration with the International Biological Program of the International Council of Scientific Unions

strengthened this.

Two parallel efforts made the voices of scientists more creditable; one

was the establishment by the Rockefeller Foundation of committees to

assess how complete were existing germplasm collections of major staple

food crops (such as rice, wheat, maize, and sorghum), and to create field

collecting teams to fill major gaps. These collections became integral parts

of collections of existing, and still to be founded, IARCs. The second effort

was a 1972 report of the U.S. National Research Council on genetic

vulnerability, which addressed the need to meet future challenges to the

adequacy of crop germplasm collections; this effort stemmed from implications of the southern corn blight epidemic. These and other efforts led to

the creation of the International Board for Plant Genetic Resources

(IBPGR) in 1974 as a center of the CGIAR, with a special relationship with

F A 0 in Rome, Italy.

The voices of crop scientists were echoed by the voices of those dealing

with forestry, and again F A 0 took the lead. Whereas initially interest was

aroused in collecting and conserving gene pools of widely used tree species, this interest is now concerned with genetic resources a p e c t s of arid

and semiarid zone forestry and desertification control, agro-silvo-pastoral

development, integrated watershed management and protection of the

resource base leading to a major initiative such as the F A 0 Tropical

Forestry Action Plan, and the call for action of a task force convened by

the World Resources Institute, The World Bank, and UNDP in 1985. A

number of these activities were foreshadowed by the consolidation in 1981

of a world conservation strategy through international conservation orga-



64



J. T. WILLIAMS



nizations. The strategy influenced the larger conservation movement to

think about plant genetic resources as integral to their activities.

Up to now these diverse activities have developed with varying degrees

of collaboration, often with recognition of common interests but, in practice, rarely with integrated scientific activities. Additionally there are now

intergovernmental activities with the F A 0 promulgating an international

undertaking and organizing a commission to oversee the implementation

of the undertaking. The terms of reference of these F A 0 endeavors cover

the wide range of plant genetic resources activities from work on crop gene

pools to nature conservation.

FOR GLOBAL

ACTIVITIES

A. THEFRAMEWORK



The programs that currently serve the needs of plant breeders and

agronomists have grown out of programs that addressed specific needs.

There were prototype genetic resources programs, which became greatly

strengthened in countries such as the United States, the Soviet Union,

Japan, the German Democratic Republic, and India; new genetic resources programs such as those of IRRI (rice), CIP (International Potato

Center; potato), CIMMYT (wheat and maize), and later those of ICRISAT,

ICARDA, IITA, CIAT, and ILCA for a range of crops and forages; and

programs initiated de n o w largely through the stimulation of IBPGR. In

the 1970s and 1980s there was the need to “build up” the collections and

IBPGR put major emphasis on supporting widespread collecting of

germplasm, due to the threat of genetic erosion, and early emphasis was on

land races and primitive varieties. This emphasis was paralleled by stimulating the establishment, or scientific upgrading, of conservation facilities

so that the materials could be stored and subsequently described. Numerous national programs became established. In the early years of IBPGR a

number of attempts to organize regional programs faltered and the operational unit emerged as the national program. The global system that rapidly

emerged resulted in the current wide array of national programs, some

weak, some strong, and also the programs of the IARCs, all loosely

federated according to mutual interest.

The past few years have pointed to the real operational units being

networked into an arrangement of institutions and scientists dealing with

the germplasm of a particular crop rather than networks of national gene

banks. It is now possible to envisage national collections as components of

dispersed world collections of genetic resources of a range of crops.

IBPGR is currently testing the feasibility of establishing such multidimensional networks by identifying participants and helping them to work



NEW DIRECTIONS IN PLANT GENETIC RESOURCES



65



together to determine the uniqueness of samples, the degrees of redundancy in collections, duplications for safety, and other joint activities.

Ironically this approach would have been a logical follow-up from the early

efforts of the Rockefeller Foundation mentioned above, but because in the

1970s and 1980s the global program was being built up with development assistance funding, a technical assistance approach was needed and

asked for.



B. AVAILABILITY

OF MATERIAL

It has been a cardinal principle that crop genetic resources should be

freely available to all users-breeders and scientists-and it has been

widely observed in the past. Some governments have adopted policies of

restricting the availability of genetic resources but these restrictions are

largely related to industrial crops such as coffee, pepper, and others. A

number of these examples-which do not accord with the international

consensus-emerged in a period when great attention was being paid to

mobilizing technology for world development. Political and economic

considerations of the consequences of technological dependence in the

least developed countries were pointing to the need to discover mutualities, to rectify the unease felt as a result of previous often shortsighted

actions, and to find new possibilities and practices in the so-called NorthSouth relationships. It is not surprising that unease at the only existing

global “system,” that of IBPGR, to make material available as an act of

voluntary collaboration was expressed in the early debates leading to the

international undertaking of FAO. There is no conflict because the whole

international community wishes to see enhanced freedom in the availability of materials, but the discussions are useful to identify the constraints on

programs in poor countries. Constraints and availability are interrelated

and because availability relates to good management of collections (Chang

et al., 1989). Additionally, there have been a number of misunderstandings

on the “values” of germplasm and potential recompense mechanisms,

which form a continuing dialogue, often to the bewilderment of the scientists involved in the practical work on genetic resources.

C. SECURITY

OF MATERIALS

Seed materials are dried and stored at low temperatures for conservation. Such conditions obviate the need for frequent grow-outs to regenerate stocks. The more stringent storage conditions (base collections)



66



J. T. WILLIAMS



ensure longer periods between regeneration and provide a degree of security. In order to avoid any disasters, duplicates are held elsewhere in other

base collections. IBPGR built up a group of centers in all parts of the world

which agreed to hold the germplasm of particular crops in base collections.

Seeds, when they can be stored, are convenient units to handle because

they have the full set of genetic information in the embryo, and most seeds

are relatively small. Seed physiology research has provided scientific

guidelines on the preparation and storage of seeds to assure long-term

viability. Research in progress is aimed generally at more cost-effective

storage, for example, the use of ultra-low seed moisture content as a

substitute for low temperatures or the use of natural environmental conditions that save energy costs.

Most of the major crops can be stored ex situ as seed in gene banks;

however, some cannot. These are either clones that cannot be reproduced

from seeds, certain trees with large seeds that have high moisture contents, or some crops that are sexually sterile. These types of materials are

conserved as vegetative material (plants) in field gene banks but their

security is not assured until better methods can be organized to maintain

them as small pieces of tissue in culture.

D. PROGRESS

ON COLLECTION

A N D CONSERVATION

OF

CROPGENEPOOLS



The major efforts on collecting germplasm, the priorities accorded over

the past 15 years, and the development of facilities to conserve the collected materials have been described in the annual reports of IBPGR, in

Williams (1985), and in Plucknett et al. (1987). These will not be reviewed

here as the purpose of this paper is to highlight new directions in the shortto medium-term future.



Ill. AREAS OF RESEARCH WHICH IMPACT PLANT GENETIC

RESOURCES WORK

A. INCREASINGPRODUCTION



The success of crop production depends on the availability of appropriate germplasm and the sources of the samples of germplasm. In addition, the manipulation of the germplasm has changed markedly in the past

100 years (Duvick and Brown, 1989). Manipulation of germplasm through



NEW DIRECTIONS IN PLANT GENETIC RESOURCES



67



plant breeding, and use of the appropriate agronomic practices (tillage,

monocultures, fertilizers, etc.) are the basis of modern agriculture. The

germplasm used routinely is largely highly selected; this is essential as new

cultivars rapidly replace each other. Breeders tend to use elite materials,

rather than primitive, relatively unselected forms such as land races,

because of the undesirable linkages in the latter. Whereas the land race

material is adapted to the site of origin, it is rarely adapted for the new

breeding aims, and additional generations of selection are not wanted by

the breeders. Despite these generalities, crop breeding strategies continually require diverse sources of germplasm, often materials of the specific

crop from widely separated geographical areas. Vavilov, the founder of

the U.S.S.R. genetic resources work, exploited this principle. It was also

an important aspect of the green revolution in cereals, for example, the

dwarf wheats bred from hybrids between East Asian and U.S. cultivars

(and the form used from Japan had in its lineage earlier U.S. cultivars).

There are two aspects to continuing production; first, efforts to maintain

stable production. and second, those to improve yield. The germplasm

collectors and the curators of genetic resources collections bear heavy

responsibilities because their decisions result in what is actually available

for breeders, even in the future.

The presence or absence of an allele can only rarely be supposed when

plants are looked at in the field. Also, variation seen by the eye may be

environmentally determined. Hence “looking for useful genes” is not

tenable. Since breeders need specific alleles to transfer in their crossing

program, should the strategy for collecting be to collect alleles (seen as a

specific character or unseen, e.g., a resistance gene), or to collect genotypes? The widely accepted practice is to collect populations of genotypes

because, in effect, breeders require certain alleles in plants that will be

used as parents with general adaptation to the environments to which the

progeny are aimed. The pragmatic decision is that germplasm available to

breeders should represent an assemblage of populations from the range of

geographies and ecologies of the crop gene pool without bias as to the

presence or absence of rare alleles. In this way the required alleles will be

present in the spectrum of genetic resources samples.

Except for a few major crops, such as rice, this strategy has rarely been

implemented since collections have been built up from amalgamation of

old breeding samples along with certain recently or newly collected

samples. As a result, the collectors and the curators have an urgent need to

“sort out” the materials and document them properly, for example, by

aggressively seeking missing collecting site data still in notebooks and by

planning targeted new collecting. In this way the samples will be more

accessible to breeders in their efforts toward continuing production.



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